The couple announced in September that HGTV's Fixer Upper will end after Season 5 in order to focus on their family and other business ventures.

"The most important thing in the world is Jo and I's relationship, followed very quickly by these four beautiful kids [of ours]," Chip said previously on Today of the decision to end the show.

"We didn't want to push it, redline it for so long that we woke up and realized we are at a point of no return," he continued. "So we wanted to take a step back and focus on what is absolutely the most important thing to us."

Joanna's younger sister Mary Kay McCall, who was featured on Tuesday night's episode of Fixer Upper, is expecting her sixth child as well.